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// run-pass
// Test a case where the associated type binding (to `bool`, in this
// case) is derived from the trait definition. Issue #21636.
use std::vec;
pub trait BitIter {
type Iter: Iterator<Item=bool>;
fn bit_iter(self) -> <Self as BitIter>::Iter;
}
impl BitIter for Vec<bool> {
type Iter = vec::IntoIter<bool>;
fn bit_iter(self) -> <Self as BitIter>::Iter {
self.into_iter()
}
}
fn count<T>(arg: T) -> usize
where T: BitIter
{
let mut sum = 0;
for i in arg.bit_iter() {
if i {
sum += 1;
}
}
sum
}
fn main() {
let v = vec![true, false, true];
let c = count(v);
assert_eq!(c, 2);
}
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